Feeler control gauge



June 23, 1931- s. E. sTocKwELL ETAL 1,811,480

l FEELER CONTROL GAUGE Filed Dec. l5, 1927 ZEW/s, f77 To R/YEY.

'reaches the desired size.

Patented June 23, 1931 [narran STATES PATENT ermeeV SIDNES. E. STOCKWELL AND ALFRED E. MURDOCK, OF HARTFORD, AND CHARLES J'. WINZIG AND ERNEST F. MORRIS, OF WEST HARTFORD, CONNECTICUT, ASSIGNORS TO 'I-IE NEW DEPARTURE MANUFACTURING COMPANY, OF BRISTOL, CONNECTICUT,

A CORPORATEON OF CONNECTCUT FEELER CONTROL GAUGE l Application filed December 13, 1927. Serial No. 239,768.

rilhis invention relates to feeler control gauges and comprises all the features of novelty herein disclosed. An object of the invention is to provide an improved feeler mechanism for actuating the electric controls oi a machine tool, such as a grinding machine. Another object is to provide improved 'feeler gauge mechanism, controlled by the size of a work-piece being machined or ground, :tor definitely stopping the machining operation at the precise instant the work Other objects are to provide mechanism for resetting the gauge parts automatically when the eeler is put in work engaging position and to improve the gauge mounting. To these ends and also to improve generally and in detail upon devices of this character, the invention also consists in the various matters hereinafter described and claimed.

In the drawings Fig. 1 is a plan view.

Fig. 2 is a side elevation.

Fig. 3 is a detail view of a securing plate.

Fig. 4: is an enlarged detail view of a cam device.

Fig. detail.

Figs. 6 and 7 are perspective views of certain details.

Fig. 8 is a side view of a feeler arm and trip lever in tripped position.

The feeler gauge mechanism of this invention is applicable generally to machine tools when it is desired to stop further machining at a definite point in accordance with the exact size of the work-piece. A feeler continuously engages the work-piece and con trols the release of an independently movable member which completes an electric circuit which may actuate a magnet or the like to control a separation of the tool and the work or stop the feed.

y In the illustrated construction, a work- 5 is an enlarged sectional view of a lpiece W, such as a sleeve or ring to be ground, is held in any suitable chuck while a grinding wheel G is fed up to it. Two feelers having diamond points engage the workpiece, preferably on diametrically opposite sides, one eeler 1() being carried on lan adjusting screw stud 12 fastened in an opening in a swingable bracket 14 and the other feeler 16 being carried on a screw stud 18 fastened in an opening of a multiplying lever 20 which swings on a conical pivot at 22 on the bracket 14:. The movement of the multiplying lever operates mechanism in a gauge housing, as will appear, to cause the electric control circuit to be completed at a definite instant. The bracket which carries the lever 20 swings on a horizontal pivot 24, the weight oi the gauge mechanism keeping the lower feeler or diamond pressed upwardly against the work. The movement of the other'feeler with. respect to the iirst measures the change in diameter of the piece' and controls the machining operation. When the work is removed, the bracket is prevented from swinging down at the rear by a stop screw 26 adjustably secured in a lug 28 on the bracket and abutting against a fork 30 which carries the pivot 24.

The pivot 24 comprises a pin projecting horizontally from the sides oit' the bracket and having recessed ends to receive pivot balls 32. One ball. is received in the recessed end of a screw 34 horizontally adjustable in one arm of the fork. The other ball is received by a recessed block 36 vertically adjustable in a guide opening 38 in the other arm of the fork by upper and lower adjusting screws 39 and 40. A plate 42 fastened by screws to the last mentioned arm of the fork holds the block 36 in its opening against the thrust of the screw 34 which adjusts the tightness of the pivotal connection and takes up play. The adjusting screws 39 and 40 enable thel block 36 to be adjusted vertically to place the pivot accurately in horizontal. The fork is carried by a conical trunnion or pivot 44 which seats in a tapered bushing 46 in a socket on a bracket 4:8 fastened to the frame of the machine. The trunnion enables the gauge mechanism to be swung laterally out of the way when inserting a piece of work in the chuck and removing it therefrom. The bracket has a handle at the rear and the lever 2O is extended at 52 to provide a thumb piece adjacent to the handle so that the operator can conveniently take hold of both to separate the eelers when swinging. the gauge mechanism to work engaging position.

The upper feeler or diamond is pressed against the work by a coil spring 54 attached to the rear end of the multiplying lever, as by the plate 55, and connected to a pin 56 on the cover of a gauge housing 58. The housing hasa side extension with a tongue 59 which is fastened by vclamping screws 60 in a groove on an upward 'extension 02 of the bracket- 14. The movement ofthe lever 20 is transmitted to parts within the gauge housing through a pointed screw pin 64 which is threaded in an opening in the lever and fastened in adjusted position by a lock nut 66. The end of the pinv 64 engages a block 68 pivoted at inv an opening of the gauge housing and having a substantially pyramidal upper portion terminating in a rounded surface or'ridge 72 which engages and actuates a lmultiplying trigger lever 74 fulcrumed at 7 6 inside the housing. rIhe block and the housing havev overlapping undercut faces at'77 so that the vopening in the housing is always substantially clos-ed. The

lever has a hardened insert .7 8 in the form of a headed pin near the fulcrum and the rounded ridgey 72 is designed to continuously engage the insert at a point lying in a line bel -tween'the fulcrum 76 and thepivot 70 so thatV they triggerY lever will have a substantially uniform angular movement under control of the feeler. The trigger lever entends lengthwise of the gauge housing and itspswinging movment i's'limited in a downward direction by a stop pin 80 and inv the upward 'direction by a stopV pinv 82.

- The endof the lever 74 carries a trigger plate 84 fastened thereto by ascrew 86; rlhe trigger plate has its upper end bent a little laterally and the bent portion has a rectangular opening 88 closed at the top by a bar 90. The bar 90 acts as a trigger to hold'a contact pin 92 out ofengagement with a contact; screw 94 until such time as the work reaches size and completes a circuit established bythe contact pin and contact screw. rllhe conta'ctpin 92 iselectrically grounded through the gauge housing the machine fram-e",being solderedon an arm 96pivoted .at 98 inthe'housing and pressed to contact making position by a leaf spring 100. It will be noted that the lever 74 does not itself di- Vrectlymake the elect-'ric Contact butcontrols the auxiliary armtl'which hasa considerable movement independently, thereby making making position and this offset construction also enables the contact pin to readily slip past the trigger bar 90 in an arc which carries it downwardly a .little as it passes through the opening in the trigger plate. The little lateral bend in the trigger plate in effect makes the lower edge of the bar 90 slant upwardly or incline with respect to its path of movementte further facilitate the sudden movement of the contact pin through the opening. y

The contact screw 94 isadjustably threaded in a brass bushing 102 insulated from the gauge housing by a fiber bushing 104 set in a boss 106 on the gauge housing 58. The contact screw is electrically connected to an insulated wire 108 in the electric circuit and is enclosed by an auxiliary housing 110 fastened to the gauge housing byy a screw 112 and also by a bent pin 114 which passes through the sides of the auxiliary housing and throughy a lug 116v on the vgauge housing. VThe inner wall of the auxiliary housing and the end of the lug 116 have opposed recesses to hold the wire 108.

A shaft 118l is rockably mounted on the gauge housing and is enlarged within the housing to receive a cross pin 120 which acts as a cam to swing the arm 96back into latched position with the contact pin 92 resting against the bar 90 on the trigger plate. The outer end of the shaft 118 is bored to receive an operating lever in the form of ai rod 122, one end of the rod forming an" operating handle and the other end having an eye 124 by which itis connected tothe feeler mechanism for automatic actuation'. Acoil spring'126 having onev end inserted in a hole inl thev gauge housing and the other endv bent around kthe rod 122 tends to move lthe cam to inoperative position. To set the trigger plate 84 and its arm 90 automatically when the feeler mechanisin is set in operative'relatioi'iy to the work, the following mechanism is provided.- A fine iieXible wire 128is`- attached-tothe eye 124 and is carried down through a notch130 in the edge of the plateV 55 fastened on the top of the multiplying lever'20. A coil spring 134 is interposed between the bottom face ofthe plate 55- and' an abutment collar 186 on the i flexible wire. Hencethe downward movenient of the rearend' of the-multiplying lever when setting the feelers pulls yieldingly on the eXible wire-*and*V rocks-theshaft 118to set the arri/100. The trigger lever 7 4 is then .free tofswing down by gravity to latching position. i f

We claim-z 1 Y 1. Ina device of the character described, a gauge housing, a lever pivotedin the'gauge housing, an arm pivoted in the housing and having an electric Contact making member,

ay cooperating contact member', a spring'l for pressing the arm'in a direction to bring the contact members* togethertocompletel an electric control circuit of the machine, a trigger bar mounted on the lever for latching or releasing the arm, a lever outside the housing and having a feeler for engaging a Work-piece during machining, means for transmitting movement from the feeler lever to the lever in the housing, and means actuated by the feeler lever for moving the arm to latched position; substantially as described.

2. In a device of the character described, a feeler for engaging a Work-piece during machining, a gauge housing having an opening, a block pivoted in the opening of the gauge housing and actuated from the feeler, and a lever pivoted in the gauge housing and continuously engaging the block at a point on a line connecting the pivot of the lever and the pivot of the block; substantially as described.

3. In a device of the character described, a feeler for engaging a Work-piece during machinin g, a gauge housing having an opening. a lever pivoted in the gauge housing, a block pivoted in the opening of the gauge housing and actuated from the feeler, and a rounded ridge on the block for engaging the lever at a point which remains substantially in the line connecting the pivot of the lever With the pivot of the block; substantially as described.

4. In a device of the character described, a feeler for engaging a Work-piece during machining, a gauge housing having an opening, a block pivoted in the opening of the gauge housing and actuated from the feeler, a lever pivoted in the gauge housing and engaging the block, and the block having a face overlapping a face on the gauge housing for maintaining the housing substantially closed during the movement of the block; substantially as described.

5. In a device of the character described, a feeler for engaging a Work-piece during machining, a gauge housing, a lever pivoted in the gauge housing and actuated from the feeler, an arm pivoted at one end in the housing and having a Contact member at its other end, a cooperating contact member, a trigger bar carried by the lever for latching the arm by engagement With the Contact member, the arm having its pivoted end offset to facilitate the release of the contact member from Y the trigger bar; substantially as described.

6. In a device of the character described, a feeler for engaging a Work-piece during `machining, a guage housing, a lever pivoted 7. Ina device of the character described, a gauge housing, an arm pivoted in the housing and having an electric contact making member, a cooperating contact member, a trigger bar for latching or releasing the arm, a feeler for engaging a Work-piece during machining, means for transmitting movement of the feeler to the trigger bar, a shaft having a cam for moving the arm to latched position, and a yielding connection from the shaft to the feeler; substantially as described.

8. In a device of the character described, a gauge housing, an arm pivoted in the housing and having an electric contact making member, a cooperating contact member, a trigger bar for latching or releasing the arm, a feeler for engaging a Workpiece during machining, means for transmitting movement of the feeler to the trigger bar, a shaft having a cam for moving the arm to latched position, an arm connected to the shaft, and a flexible Wire connecting the arm to the feeler; substantially as described.

9. In a device of the character described, a gauge housing, an arm pivoted in the housing and having an electric contact making member, a cooperating contact member, a trigger bar for latching or releasing the arm, a feeler for engaging a Work-piece during machining, means for transmitting movement of the feeler to the trigger bar, a shaft having a cam for moving the arm to latched position, an arm connected to the shaft, a flexible Wire connected to the arm of the shaft and having a collar, and a spring interposed between the feeler and the collar; substantially as described.

10. In a device of the character described, a gauge housing, an arm pivoted in the housing and having an electric contact making member, a cooperating contact member, a trigger bar for latching or releasing the arm, a feeler for engaging a Work-piece during machining, means for transmitting movement of the feeler to the trigger bar, a shaft having a cam for moving the arm to latched position, an arm connected to the shaft, a notched plate connected to the feeler, a flexible Wire connected to the arm of the shaft and passing through the notch of the plate, and a spring between the bottom of the plate and the end of the Wire; substantially as described.

11. In a device of the character described, a swingable bracket having a feeler for engaging one side of a. Work-piece being machined, a lever pivoted to said svvingable bracket and having a feeler for engaging the opposite side of the Work-piece, one end of the lever and one end of the bracket extending in close proximity to one another to facilitate separation of the feelers from the Work-piece, a gauge housing carried by the svvingable bracket, mechanism in the gauge housing for completing an electric control circuit of the machine, and means for operating said mechani'sm from the lever; scribed.

substantially as def *'12. In a device of theV character described,

bracket having a eeler for engaging one side of a work-piece being machined, a lever pivoted to said bracket and having a feeler for engaging the opposite side of the work-piece, a member for supporting the bracket to swing on a horizontal axis, said member having a vertical pivot to allow the eelers to be swung laterally of the work, a gauge housing carried by the bracket, mechanism in the 'gauge housing for completing an electric control 4circuit of the machine, and means for operating. said mechanism from the lever; substantially as described.

In testimony whereof we hereunto aPX olir y signatures. f SIDNEY E. STOCKWELL.

ALFRED E. MURDOCK. CHARLES J. WINZIG. ERNEST F. MORRIS. Y 

